I often read this passage over the shoulders of the original audience and of Jesus himself, as though I am the servant being addressed. I know, in at least some small measure, what it is to have an "instructed tongue," an "awakened mind," and "opened ears" — all to the end of speaking a "word that sustains the weary." Reading on in the passage, however, my appropriation of the text drops away as I recognize with reverence and grief the humiliated and beaten One who is the Suffering Servant.
Echoes from this passage abound in the New Testament: Jesus' withdrawal into quiet places for prayer (Lk 5:16) and his resolute face set toward Jerusalem as his earthly ministry draws to a close (Lk 9:51); descriptions of Jesus' physical suffering during his trial and crucifixion; and the Apostle Paul's rhetorical question "Who will bring any charge against those whom God has chosen?" (Rom 8:31-34) — all stem from this prophetic passage, encompassing us it does so many aspects of Jesus' ministry.
The passage ends with a stern exhortation. The example of this One – the Instructed Servant, the Listening-Before-Speaking Servant, the Early-Rising Servant, the Resolutely Obedient Servant, the Suffering Servant — rebukes any shortcuts on the path of obedience. We are encouraged to accept times of darkness and suffering as the Perfect Servant does in trustful obedience to — and full reliance on — a God whose perfect will is being worked out. Even in the dark.